Hongyin Zhang, Qiya Yang and Lina Zhao
Jiangsu University, P R China
Posters & Accepted Abstracts: Arch Clin Microbiol
The efficacy of Pichia caribbica in controlling postharvest blue mold and natural decay development of apples and degrading the patulin were investigated. The decay incidence of the blue mold of apples treated by P. caribbica was significantly reduced compared with the control samples and the higher the concentration of P. caribbica, the better the efficacy of the biocontrol. P. caribbica significantly controlled the natural decay development of apples following storage at 20°C for 35 days or 4°C for 45 days followed by 20°C for 15 days. Germination of spores and growth of Penicillium expansum were markedly inhibited by P. caribbica in in vitro test. Rapid colonization of apple wounds by the yeast was observed in fruit stored at 20°C or 4°C. After incubation with P. caribbica at 20°C for 15 days, patulin production by P. expansum in apples was significantly reduced compared with the control. In vitro test indicated that P. caribbica can degrade patulin directly. Our results suggested that the mechanism of degradation of patulin by P. caribbica was not absorption; the presence of patulin can induce P. caribbica to produce associated intracellular and extracellular enzymes, both of which have the ability to degrade patulin. The result provides a new possible method that used the enzymes produced by yeast to detoxify patulin in food and feed.